1. Field of the Invention
The present invention relates to building assemblies having standing seam sidelap systems, and more particularly but not by way of limitation, to an improved standing seam sidelap metal roof. In one aspect, the present invention relates to an improved panel and a method for assembling panels to form a standing seam sidelap metal roof.
2. Discussion of Prior Art
The pre-engineered building industry has developed into a very large segment of the building construction industry in the United States, and it has experienced an increasingly greater share of the construction industry budget throughout the world. The established method of erecting the roof or wall of a pre-engineered building is to erect the building frame which is comprised of primary and secondary structural members supported by a foundation. Once the foundation is constructed, the primary structural members are erected and attached to the foundation; next, the secondary structural members are connected across the primary structural members. Appropriate bracing members are interconnected, and roll blanket insulation is placed either across or parallel with the secondary structural members and temporarily secured in place by weights or some other securing means.
The panel members are then disposed over the blanket insulation, and the panel members and underlying secondary structural members are connected together by fasteners. Typically, the attachment of roof panel members is done by workmen who stand on top of the panel members and attach the panel members to the underlying secondary structural members (which will usually be purlins or bar joists). The panel rests substantially on the underlying secondary structural member.
The purpose of connecting the panel to the secondary structural member is to secure the panel members and to transfer externally imposed load from the panel members to the secondary structural members, which in turn transfers the stress to the primary structural members. These imposed loads create stress which may be tension, shear or compressive stress. As to the latter, compressive stress is created by inwardly directed live load which is transferred through the blanket insulation.
Numerous types of roof assemblies have heretofore been proposed for a pre-engineered building in an effort to provide a watertight roof assembly, while at the same time enabling the roof assembly to expand and contract as changes in temperature are encountered. Typical of such a prior art roof assembly which has met with considerable success in recent years is the standing seam roof assembly. The panel members of the standing seam roof assembly are joined to each other along adjacent sides such that the sides are lapped together to form the standing seams. The panel members of the standing seam roof are secured to the secondary structural members by means of clips. The interconnection of the panel members of the standing seam roof lend stiffness and strength to the roof structure, while allowing the roof structure to expand and contract as a function of the coefficient of expansion of the materials of which the roof panels are made and the temperature cycles to which the roof panels are exposed.
The repeated action of expansion and contraction on the panel members of the roof assembly tends to weaken the panel-to-panel-to-lap joint and often causes panels to separate or structural failure and leaks in the roof assembly. The leaks are generally caused by the weakening of the fastening members and working or kneading of the sealant used at the joints. In many of the prior art roof assemblies, the sealant employed required adhesion, flexibility and water repellency. Further, the design of the joint was in many instances such that the pressure on the sealant varied greatly throughout the length of the sidelap and endlap joints of the panels and resulted in uneven distribution and/or voids of the sealant in the joints which frequently led to leaks.
Many of the before-mentioned problems encountered in the prior art standing seam roof assemblies, such as structural failures and leaks, have been overcome by the improved standing seam metal floating roof assembly disclosed in copending U.S. patent application Ser. No. 425,477, filed Sept. 28, 1982 by Harold G. Simpson and Bert D. Hollman, and now U.S. Pat. No. 4,497,151 issued Feb. 5, 1985. standing seam floating roof assembly of the before-mentioned copending patent application is formed of elongated metal panels, each of which is provided with a female member formed along one side portion of the panel and a male member formed along the opposed side portion of the panel such that adjacent panels are interlocked with the female and male members thereof to form the standing seam. A clip having a slidable upper portion is secured between the standing seam of the roof assembly and the secondary structure such that the upper portion of the clip is disposed between the male and female members of the panels forming a standing seam. The clip is further constructed so that relative motion between the clip and the metal panels is substantially prevented. To assist in the watertightness of the standing seam a resilient material is disposed in the upper portion of the standing seam between the female member and the male member.
The structure and features of the improved standing seam floating roof assembly disclosed in the before-mentioned patent application achieves the objective of providing an improved watertight standing seam floating roof assembly wherein the resilient material is clamped between adjoining male and female members of the panels without the aid of a field-seaming machine or the necessity of assembling and rotating the panel being assembled into a pre-designated position. However, problems may nevertheless be encountered due to human involvement in the construction of the standing seam roof assembly, especially in the formation of a watertight, structurally sound, quality-consistent standing seam by the union of the male member of one panel with the adjacently disposed female member of a second panel. Further, separation of the standing seam (i.e. the union found between the male member of one panel and the female member of the adjacently disposed panel) may result when the panels are subjected to differential loads, such as may be encountered when one panel expands or contracts differently than an adjacent panel, or when an uplift load, such as may be created by wind, is encountered by the panels forming the standing seam roof assembly. Thus, a need remains for an improved panel and standing seam roof assembly wherein the watertightness and structural integrity of the standing seam is not adversely affected when diverse loads are applied to the panels forming the standing seam, as well as a method for assembling such an improved standing seam roof assembly which substantially eliminates human error encountered in the formation of the standing seam by union of adjacent panels via the male and female members of the standing seam, and enables one to more readily provide for proper alignment and improved structural engagement of the male and female members of the standing seam so as to improve the joint integrity of the standing seam.